1. Technical Field
The present invention relates to a process for preparing compounds of general formula I which is based on a stepwise synthesis starting from compounds of general formulae III and IV. In addition, the invention relates to the compounds of general formulae III and IV per se, as these are particularly suitable for preparing the compounds of general formula I which have CGRP-antagonistic properties.
2. Prior Art
International Patent Applications PCT/EP03/11762 and PCT/EP2005/003094 have already described compounds with CGRP-antagonistic properties as well as some laboratory synthesis methods for preparing small amounts.
In addition, a process for preparing 3-(4-piperidinyl)-2,3,4,5-tetrahydro-1,3-benzodiazepin-2(1H)-one is described in European Patent Application No. 04017424.5.